1. Field
The following description relates to a packet routing apparatus and method for reducing power consumption and packet transmission delay in a sensor network, and more particularly, to a packet routing apparatus and method that may intervene on a relay transmission path of a data packet.
2. Description of Related Art
A sensor network may include a home sensor network, a structure monitoring network, a healthcare network, and the like. The sensor network may include one or more nodes that are operated by batteries for costs and convenience of installation.
Accordingly, a large number of methods for low-power communication in a sensor network have been designed. For example, a synchronous medium access control (MAC), an asynchronous MAC, and the like, have been proposed to perform idle listening in nodes at regular wakeup intervals.
The synchronous MAC may include, for example, an Institute of Electrical and Electronics Engineers (IEEE) 802.11 Adhoc, a S-MAC, and the like. Among the asynchronous MAC, a transmitter oriented asynchronous MAC may include, for example, a B-MAC, an X-MAC, and the like, and a receiver oriented asynchronous MAC may include, for example, a receiver-initiated MAC (RI-MAC), and the like.
In a sensor network, a data packet to be relayed is typically small in size, and the sensor network is sensitive to power consumption that is caused by idle listening. The idle listening also causes a transmission delay because often a relay node may be in a sleep state while a node is attempting to transmit a data packet to the node in the sleep state. This waiting can cause a delay in transmission time.